These reports present the main results of a serological population survey related to the corona epidemic of the Department of Health and Welfare. The study investigates the spread of the new coronavirus (SARS-CoV-2) in Finland and the extent and properties of the antibody formation (immunological resistance) caused by it. The main purpose of the study is to determine up-to-date the proportion of the population in different age groups and regions with coronavirus antibodies (so-called seroprevalence) as a sign of viral exposure, i.e. symptomatic or asymptomatic coronavirus infection. The participants of the study are selected by random sampling from different parts of Finland and a blood sample is taken in the study for the examination of antibodies. The results page is updated about every two weeks.